import cv2
import matplotlib.pyplot as plt
import numpy as np
img=cv2.imread('CV-Pictures/chessboard.jpg')
gray=cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
edges=cv2.Canny(gray,50,150)
lines=cv2.HoughLinesP(edges,1,np.pi/180,1,minLineLength=100,maxLineGap=10)
img3=img.copy()

for line in lines:
    x1,y1,x2,y2=line[0]
    cv2.line(img3,(x1,y1),(x2,y2),(255,0,0),2)

cv2.imshow('img',img)
cv2.imshow('Hough_Lines',img3)
cv2.waitKey()
cv2.destroyAllWindows()